Hello Benoir, I agree with the translation of 'alot' by 保奈美 san. Then, I will try to explain further below. First of all, please be understood that this phrase is a slang used among the young. The phrase されまくっている can be separated into される + まくっている. You know, される is the passive form of verbs, or means 'be ..ed' So the part 尊敬される means 'be respected'. まくっている is the present continuous tense of まくる(捲る). Here まくる followed by a verb express that the act of the verb is done with great force, vigorous, powerfully, or energetically etc. And used here to emphasize the act of the verb to a great extent. And simply translated into like 'alot', 'so much', 'a great deal' etc. So the literal interpretation of this 尊敬されまくっている is 'someone(or something) is being respected vigorously'. And it represents that someone is respected a great deal(alot).

Hmmm , its like getting alot of ... in this case respect. they respect him ALOT, alot ... here ~されまくっている